Abstract：Ochratoxin A(OTA) is a widespread mycotoxin. It can contaminate cereals, animal feed, animal foodstuffs et al. OTA has been shown to be nephrotoxic, hepatotoxic, teratogenic, immunotoxic, mutagenesis and carcinogenesis to several species of animals. The plant toxicity of OTA has been discovered in recent years. In this research we focused on the involvement of salicylic acid(SA) in OTA toxicity to Arabidopsis thaliana, which is an important endogenous signal molecule of plants. SA content of A.thaliana leaves exposed to OTA was measured by high performance liquid chromatography. The results showed that OTA treatment increased SA content in A.thaliana leaves. Quantitative Real-time PCR was performed to determine the relative expression level of pathogenesis-related gene 1(PR1) which is an important gene in SA pathway. We found that PR1 expression was induced by OTA, moreover the effect of OTA was related to treatment time. When exogenous SA was treated with OTA, aggravated lesions were observed. According to results of relative leakage rate and reactive oxygen species content measurement, it was showed that SA could enhance the damage of leaves and promote reactive oxygen species production caused by OTA. The research indicates the involvement of SA in plant toxicity of OTA which can be enhanced by SA.
